A former chairman of the Youth Justice Board today dismissed Gordon Brown's latest initiative to reduce teenage knife crime as a gimmick that only served to display the Prime Minister's own political weakness.

Mr Brown gathered ministers and top officials at Downing Street today for a breakfast meeting to discuss the new Home Office policy – which comes into effect today – under which 16- and 17-year-olds caught with a knife can expect prosecution for the first offence.

Under current guidelines they can expect to escape with a caution but the Prime Minister decided to review that policy after a spate of high-profile stabbings by and of teenagers.

Emerging from the 40-minute meeting this morning, Mr Brown told reporters: “Carrying a knife is completely unacceptable. When any young person or teenager who is encouraged to carry a knife is not making themselves safer, they are all making it more likely crimes are committed.

"We have got to make sure if a young person is carrying a knife, there is a message they will end up in court. They are putting other children and young people at risk.”

Also attending the meeting at No 10 were Jacqui Smith, the Home Secretary, Jack Straw, Justice Secretary, Baroness Scotland, the Attorney-General and the Sussex Police Chief Constable Ken Jones, who is the president of the Association of Chief Police Officers.

But even as they met, Professor Rod Morgan, who resigned as chairman of the Youth Justice Board last year to protest against government policies, attacked the new guidelines for police and prosecutors.

“I am afraid this is an example of gesture politics reflecting the weakness rather than the strength of both the Prime Minister and the Government,” Professor Morgan told BBC Radio 4’s Today programme.

“There is no real good sense in suggesting that the guideline be changed. Isn’t it odd that last week we had an announcement that four police forces are going in the future to do something called ’commonsense’ policing ... that the police were going to exercise their discretion more sensibly as to how events should be dealt with locally, and now we have a suggestion that we have a presumption?

“The police have all the powers that they need to deal with what is a problem in some areas but they need to be given discretion to respond to events as they find them.”

Mr Jones, the Acpo head, insisted that officers would still exercise “common sense and discretion” but said there was no good reason for any young person to be carrying a knife.

“The individual officer will, and I will defend their right to, use their discretion and common sense but the point at which they now would consider this individual has no previous conviction, there are no aggravating factors, that he or she might be subject to a caution, we are now saying no, that is now removed.”

He said that his message to young people was: “If you don’t want to get yourself into court, don’t carry. And work with us in your neighbourhood to remove the factors which cause you to be fearful which cause you to carry knives.

“And those who carry for more unlawful purposes: we will go after you as hard as you possible can.”

Mr Jones said that it was important to “get a sense of proportion” about the scale of the problem. “But there is a problem, there is an issue, which is why we support this move whereby we are sending out a message to young people: if you carry knives without good reason, you can expect us to try and get you to court.

“We are not out to criminalise young people who have a good reason for being in possession of a knife, but frankly what good reasons would a youngster have to carry even a penknife?"

Yesterday Mr Brown told the House of Commons that parents also needed to be responsible for telling their children not to carry knives. He told MPs: “Every parent will want their teenage sons and daughters not only to be safe but to feel safe in our neighbourhoods. That’s why knives are unacceptable and we’ve got to do everything in our power to deter them.”

The new guidelines are accompanied by a series of other measures, including an advertising campaign aimed at deterring young people from carrying knives. Ms Smith said that information would be provided to help parents broach the subject.

Last week the Metropolitan Police Commissioner Sir Ian Blair, who did not attend today’s meeting, pledged to continue a controversial crackdown which has seen police in London using section 60 powers to stop and search people even if they have no suspicion that they are carrying a knife.

Critics have said that continued use of the powers could aggravate police relations with the community. Sir Ian said the crackdown, called Operation Blunt, will stop when murders reduce. Sixteen teenagers have been killed so far this year in the capital.

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